Buy a Kindle book from your Mac, PC, or iPhone using a Web browser and wirelessly transfer the books to your iPhone

Read first chapters of any book for free before you buy

Download the Kindle books you already own for free -- they are automatically backed up on Amazon.com

Adjust the text size, add bookmarks, and view the annotations you created on your Kindle device

The iPhone client will also allow you to seamlessly switch back and forth between your Kindle device and Kindle for iPhone while keeping bookmarks and reading location synced between the devices. The Kindle is Amazon's electronic book reader that was recently updated to version 2. Amazon had promised that Kindle content would become available for mobile phones which had led to speculation that they might support the iPhone.

Very nice. You can get the free app here. You can get the Kindle 2 here.